This invention relates to the discovery and asexual propagation of a new variety of grapevine, Vitis vinifera cv. xe2x80x98Sugratwentytwoxe2x80x99. The new variety was first hybridized by David W. Cain in Wasco, Kern County, Calif., the variety being originated by controlled hybridization and subsequent embryo rescue of abortive seed traces. The new variety is characterized by white, medium sized seedless berries that are crisp and are oblong in shape. The new variety produces larger berries in response to gibberellic acid application, and is extremely productive when pruned to short spurs.
The seed parent is xe2x80x98Sun World Breeding Selection 89152-064-236xe2x80x99 (unpatented) and the pollen parent is xe2x80x98Sun World Breeding Selection 89134-202-189xe2x80x99 (unpatented). The parent varieties were first crossed in May, 1993, with the date of first flowering being May, 1995. The new xe2x80x98Sugratwentytwoxe2x80x99 variety was first asexually propagated by David W. Cain in December, 1995 in Wasco, Kern County, Calif., using hardwood cuttings.
The new grapevine variety cv. xe2x80x98Sugratwentytwoxe2x80x99 resembles its seed parent xe2x80x9889152-064-236xe2x80x99 in outward appearance, but differs by producing berries with superior eating quality, containing higher sugar and lower acid content than in the maternal parent. xe2x80x98Sugratwentytwoxe2x80x99 is distinguished from the pollen parent, xe2x80x9889134-202-189xe2x80x99 by being more elongated, in addition to exhibiting better harvesting and shipping characteristics due to its stronger, more lignified peduncle, rachis, pedicel and torus that function to attach the berries more strongly to the cluster.
The new xe2x80x98Sugratwentytwoxe2x80x99 is distinguished from other commonly grown grapes such as the xe2x80x98Autumn Seedlessxe2x80x99 (unpatented) and the xe2x80x98Thompson Seedlessxe2x80x99 (unpatented) varieties. The xe2x80x98Sugratwentytwoxe2x80x99 most nearly resembles the xe2x80x98Autumn Seedlessxe2x80x99 variety, but is distinguished from the xe2x80x98Autumn Seedlessxe2x80x99 variety by producing crisp berries that have a creamy yellow green color. The xe2x80x98Autumn Seedlessxe2x80x99 variety, in contrast, produces berries of less commercially acceptable darker green color that turn pink when exposed to direct sunlight. Moreover, while the yields of the xe2x80x98Autumn Seedlessxe2x80x99 variety are often low, the new xe2x80x98Sugratwentytwoxe2x80x99 variety possesses a fruitful vine that is more capable of producing commercially acceptable yields.
xe2x80x98Sugratwentytwoxe2x80x99 bears a slight resemblance to the xe2x80x98Thompson Seedlessxe2x80x99 variety but is distinguished from the xe2x80x98Thompson Seedlessxe2x80x99 variety by several important characteristics. The new variety xe2x80x98Sugratwentytwoxe2x80x99 produces berries that are more crisp and naturally larger than the xe2x80x98Thompson Seedlessxe2x80x99 variety. xe2x80x98Sugratwentytwoxe2x80x99 berries have a stronger attachment to the cluster, and are more resistant to adverse weather conditions than the xe2x80x98Thompson Seedlessxe2x80x99 variety. The vestigial seeds of xe2x80x98Sugratwentytwoxe2x80x99 are slightly larger than the vestigial seeds of the xe2x80x98Thompson Seedlessxe2x80x99 variety. Additionally, xe2x80x98Sugratwentytwoxe2x80x99 berries can be allowed to stay on the vine much later, as they ripen approximately 60 days later than the xe2x80x98Thompson Seedlessxe2x80x99 variety.
The new xe2x80x98Sugratwentytwoxe2x80x99 variety has been shown to maintain its distinguishing characteristics through successive asexual propagations by, for example, cuttings.